IS IOVO VULNERABLE TO A DOUBLE-PARASITE CHAIN ATTACK?

No. A double-parasite chain attack is a characteristic of a particular single-transaction DAG: IOTA’s Tangle. IOVO uses a different approach, called multi-blockchain DAG with proof-of-stake. This setup is immune to the double-parasite chain attack, simply because the proof-of-stake algorithm prevents every user with less than 50% stake from performing a double-spend attack.https://iovo.io